Abstract
In the present work, ultrathin films of Zinc oxide (ZnO) and Aluminum doped zinc oxide (AZO) with 20 nm thick were fabricated at 300 K on glass and Polyethylene terephthalate (PET) substrates by means of direct-current sputtering method. The structural morphology of the films were analyzed by (XRD) diffractometry. The average transmittance of films deposited on different substrates showed high transparency (over 80%) in the visible spectrum. The objective of the present work is to investigate the thicknesses and optical constants of ZnO and AZO ultrathin films prepared by DC sputtering onto (glass and PET) substrates using two methods (UV–Vis–NIR spectrophotometer and ellipsometer (SE) by new amorphous dispersion formula) with comparison to check and confirm the results that obtained from UV with those obtained from SE measurements. The optical constants of films were extracted and compared using UV and SE techniques in the range of (200–2200 nm) with increment of 1 nm in order to confirm the accuracy of the UV and shown an excellent agreement.
Similar content being viewed by others
References
Azzam, R.M.A., et al.: Ellipsometry and polarized light. North-Holland, Amsterdam (1981)
El Manouni, A., et al.: Effect of aluminium doping on zinc oxide thin films grown by spray pyrolysis. Superlattices Microstruct. 39(1), 185–192 (2006)
Forouhi, A.R., et al.: Optical dispersion relations for amorphous semiconductors and amorphous dielectrics. Phys. Rev. B 34(10), 7018–7026 (1986)
Forouhi, A.R., et al.: Optical properties of crystalline semiconductors and dielectrics. Phys. Rev. B 38(3), 1865–1874 (1988)
Hagendorfer, H., et al.: Highly transparent and conductive ZnO: Al thin films from a low temperature aqueous solution approach. Adv. Mater. 26(4), 632–636 (2014)
Hasnidawani, J.N., et al.: Synthesis of ZnO nanostructures using sol-gel method. Proc. Chem. 19, 211–216 (2016)
HORIBA Jobin Yvon. Spectroscopic ellipsometry user guide. France, pp. 122, 196 (2005)
Jellison Jr., G.E., et al.: Parameterization of the optical functions of amorphous materials in the interband region. Appl. Phys. Lett. 69(3), 371–373 (1996)
Jeong, S.H., et al.: Al-ZnO thin films as transparent conductive oxides: synthesis, characterization, and application tests. J Korean Phys. Soc. 50(3), 622–625 (2007)
Kluth, O., et al.: Modified thornton model for magnetron sputtered zinc oxide: film structure and etching behaviour. Thin Solid Films 442(1), 80–85 (2003)
Lee, T.-H., et al.: ZnO and conjugated polymer bulk heterojunction solar cells containing ZnO nanorod photoanode. Nanotechnology 22(28), 285401–285406 (2011)
Li, X.-Y., et al.: Effect of substrate temperature on the structural and optical properties of ZnO and Al-doped ZnO thin films prepared by dc magnetron sputtering. Optics Commun. 282(2), 247–252 (2009)
Ma, J., et al.: Comparison of the electrical and optical properties for SnO2:Sb films deposited on polyimide and glass substrates. Appl. Surf. Sci. 214(1), 208–213 (2003)
Mang, A., et al.: Band gaps, crystal-field splitting, spin-orbit coupling, and exciton binding energies in ZnO under hydrostatic pressure. Solid State Commun. 94(4), 251–254 (1995)
Messaoudi, O., et al.: Correlation between optical and structural properties of copper oxide electrodeposited on ITO glass. J. Alloys Compd. 611, 142–148 (2014)
Minami, T.: Transparent conducting oxide semiconductors for transparent electrodes. Semicond. Sci. Technol. 20(4), S35–S44 (2005)
Nishino, J., et al.: Preparation of aluminum-doped zinc oxide films by a normal-pressure CVD method. J. Am. Ceram. Soc. 75(12), 3469–3472 (1992)
Palik, E.D.: Handbook of optical constants of solids, Chap. 7, vol. 3. Academic, Orlando (1998)
Tauc, J., Grigorovici, R., et al.: Optical properties and electronic structure of amorphous germanium. Phys. Status Solidi (b) 15(2), 627–637 (1966)
Wang, F.-H., et al.: Effects of H2 plasma treatment on properties of ZnO: Al thin films prepared by RF magnetron sputtering. Surf. Coat. Technol. 205(23), 5269–5277 (2011)
Zang, Z., et al.: Single cuprous oxide films synthesized by radical oxidation at low temperature for PV application. Opt. Express 21(9), 11448–11456 (2013)
Zang, Z., et al.: Strong yellow emission of ZnO hollow nanospheres fabricated using polystyrene spheres as templates. Mater. Des. 84, 418–421 (2015)
Zang, Z., et al.: Femtosecond laser direct writing of microholes on roughened ZnO for output power enhancement of InGaN light-emitting diodes. Opt. Lett. 41(15), 3463–3466 (2016)
Zhang, Q., et al.: ZnO nanostructures for dye sensitized solar cells. Adv. Mater. 21(41), 4087–4108 (2009)
Ziang, X., et al.: Refractive index and extinction coefficient of CH3NH3 PbI3 studied by spectroscopic ellipsometry. Opt. Mater. Express 5(1), 29–43 (2015)
Acknowledgements
Authors are grateful to Nicolas Mercier, Magali Allain for providing the necessary facilities for XRD studies, Also, to Jean-Paul Gaston and Celine Eypert from Jobin–Yvon Horiba Company for the spectroscopic ellipsometry measurements and to Cecile Mézière, Valerie BONNIN for help with the chemicals and corresponding equipment.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Rasheed, M., Barillé, R. Room temperature deposition of ZnO and Al:ZnO ultrathin films on glass and PET substrates by DC sputtering technique. Opt Quant Electron 49, 190 (2017). https://doi.org/10.1007/s11082-017-1030-7
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11082-017-1030-7